A number of devices for facial recognition are present in the market today, such as the facial recognition systems made by Identix Inc., of Minnetonka, Minn., and Neven Vision, of Santa Monica, Calif. Most of these systems make use of one or both of two main facial feature detection algorithms, eigenface and local feature analysis, and generally work by first recognizing a face in general and then performing feature measurements to find corresponding matches in a data base. To recognize a face in general, multi-scale algorithms are used to search a field of view at a low resolution in order to detect a general facial shape. Once the facial shape is detected, alignment begins in which the head position, size, and pose are determined. An image is then normalized and facial data is translated into a unique code, which allows for easier comparison to stored data.
One limitation of the above systems is that the face must be angled at a certain angle toward the camera, for example, 35 degrees and above, for the image to be taken. Furthermore, since most of these systems only examine geometrical shapes, sizes, and locations of facial features, they cannot easily tell the difference between a real person's face and a rubber mode or photograph of the person's face, and can thus be easily fooled by someone attempting to bypass a security system utilizing one of the facial recognition systems.
Another limitation is that these systems are not scalable and can only be used in a limited number of devices. Cameras are now available in various information appliances, such as cellular phones, personal digital assistants (“PDAs”), notebook computers, digital music players, among others. To date, there is no facial recognition system that can be used in a multitude of portable devices for basic identification purposes or to improve security at a given location.
There is therefore a need for a more precise facial recognition method and system that are not susceptible to the above types of fraud.
There is also a need for a facial recognition method and system that can be used in portable devices.